Variable oscillating gear



May 22, 1951 J. D. KREIS VARIABLE OSCILLATING GEAR IIII' 4 Sheets-Sheet1 5 m m V mm 7. A

Filed Oct. 9, 1946 May 22, .1951 J. 0. KREIS 2,553,359

' VARIABLE oscmmmcmx Filed Oct. 9, 1946 v 4 Sheets-Sheet 2 INVEN TOR.JOSEPH 0. [(3518 ATTOBNE Y8 y 1951 J. D. KREIS 2,553,859

VARIABLEDSCILLATING GEAR Filed Oct. 9, 1945 4 Sheets-Sheet s 5 i IINVENTOR.

JOSEPH D. KEE/S f/?TM TTOBNEYS May 22, 1951 J. D. KREIS VARIABLE oscmnmcGEAR '4 Sheets-Sheet 4 Filed Oqt. 9, 1946 INVENTOR. JOSE PH D. KeE/SATTOBA/[YS Patented May 22, 1951 UNITED STATES PATENT 7 OFFICE VARIABLE'OSGILLAT IN G GEAR Joseph D. Kreis, Gleveland, Ohio ApplicationOc'tbber'l), 1946, Serial No. 702,154

17 Claims.

This invention relates to variable oscillating gear mechanisms, that:is, devices for converting continuous rotary motion into'oscillatingrotary motion, having a provisioncfor varying the amplitude of theoscillating motion. In its preferred embodiment, as described herein,the invention is applied to a drive for the agitator of a washingmachine, but, as will be seen, the mechanism may be employed in variousenvironments.

An object of the invention is to provide a mechanism for convertingcontinuous rotary motion into oscillating rotary motion.

Another object of the invention is to provide such a mechanism in whichthe amplitude of the oscillating movement may be varied while themechanism is'in ope-ration.

Another object of the invention is to provide means for rotationalcoupling between two bodies having offset axes of rotation.

Another object of the invention is to provide a mechanism for convertingcontinuous rotary motion into oscillating-rotary motion which will becompact, reliable and durable, and will be economical of manufacture.

Another object isto provide a mechanism which is adapted for enclosurein a driven rotat able housing which may be sealed and contain a bath oflubricant.

A further object of the invention is to provide an improved drivingmechanism for a washing machine agitator.

Other objects and advantages more or less ancillary to the foregoing andthe manner in which all the vvarious objects are realized will appear inthe following description, which, considered in connection with theaccompanying drawings, sets forth the preferred embodiment of theinvention.

Referring to the drawings:

Fig. l is an elevational view, partly in section, illustrating theapplication of the invention to a washing machine;

Fig. 2 is a sectional view of a fragmentary por tion taken on a planeindicated on a line 2-'2' of Fig. 1;

Fig, 3 is a plan view o f'a portion of the'mechahis-m showing theeccentric planet gear;

Fig. 4 is a view of the concentric planet gear as seen from below;

Fig. 5 is a vertical section through the planet gears taken on a planeindicated by the lines 5--'5 in Fig. 3; and

Fig. 6 is a vertical section through the planet gears taken on a planeindicated by the line 6 -6 in- Fig. 3.

Referring. to-Fi'g. -1=, the-invention is illustrated as incorporated ina: conventional washing ma chine having a tub H n-iounted on a framei2and including. a drive pulley I3 associated-l with a motor (not shown)and a: power tahe-offipulleyl t for the operation: of a wringer (notshown-L The gearing which for-ms the subject of thislin-e. ventionis'principally enclosediina housing- 45in the iorm of a hollow pulley.The agitator shaft ripheral grooves therein mime retention. of the 52extendsupward from the housing through a gland in the bottom. of thetub. The housing [5 comprises two flanged sheet metal stampings l6 andI? lFigs. 1. and 6) which are annular inform and struck with. themarginal portions thereof:

directed inwardly tof'orm the sides 3 015 a vebelt pulley. when the twostampings are assembled:

opposed relation to .eachtother. The two-stampe ings it and. [1. are.retained in, clamped; relation by conical-headetlscrews l9-1 seatedinopenings 21 in. the stampih'gs and threaded intospacinga,

sleeves 22. A gasket 23-, preferably composed of synthetic rubber, isclamped between the opposed edges of the flanges 3., providing a sealagainst leakage of. oil from the housing. The lower hub. 260i thehousing l5.is.iormedaby a frustoeco'nical malleable casting. havingaperipheral groove 21-.

therein. for the reception of the circumsference of the stamping. Thewalls of: the caste ing 2e. defining the groove 21 are rolled orpressedinto intimate toil tight engagement with the The,

stamping l? to client the support thereof. upper hub 28 is sealed intothe upper stamping It in the same manner. Thehub 28 is provided with acounterbored central opening 29 into which is ressed a flanged bushing30 which forms a radial and thrust bearing surface rcr rotationalsupporter the housing l5. The bush m 30 is jourhall'ed on a flangedsleeve 3-!- threaded ontoa depending cylindricalportion 32 or; a spider33. The pider is formed with a cylindrical flange 3'4 cireur'njacent thehub 21? which defines a pocket between the flange and hub for theretention of packing 36. The-spider 33 is further formed with apluralityof equallyspaced ears '3! having cups 313- in theextreinities- Capscrews;

marginal edges of openings 4! in the frame member I2. The agitator shaft42 is sealed against leakage by packing 48 retained by a sleeve 49threaded into a cup 58 formed in the central portion of the bearingmember 4|. The bottom of the tub is retained between a flange 5Ia of thecasting and a nut 52 threaded onto the sleeve 49. The agitator shaftpasses through an opening 53 in the bottom of the cup 59, through thecasting 33 and into the housing I5.

The agitator shaft is driven by a sun pinion 56 (Fig. 6) formed integralwith a sleeve 5'! splined to the lower end of the shaft (Fig. 1) andretained by a spring collar 58. The lower end of the shaft 42 isjournaled in a flanged bushing 59 pressed into a bore in a centralcylindrical portion 6! of the hub casting 26/ A thrust washer 62, keyedto the sun pinion, by a tab which is bent for engagement between teethin the face of the'pinion, is interposed between the pinion and thethrust bearing face of the bushing 59.

Oil may be drained from the housing through a passage 64 in the hub 26by removing a plug 66 at the bottom of the hub. A plug 61 threaded intothe upper stamping I6 of the housing is provided to facilitatereplenishment of the oil. The mechanism preferably runs in a bath ofoil.

.'The oscillating gear contained in the housing I5 is based upon theprinciples disclosed in my copending application Serial No. 667,965,filed May 7, 1946, for Oscillating gear. In accordance with theprinciples therein set forth, the present apparatus includes a fixed sunpinion 93 mounted inthe spider 33 and in coaxial relation with theagitator shaft 42 and the agitator sun pinion 56. Aplanet gear 81 isconcentrically mounted with respect to and engages the fixed sun pinion93, the housing I5 serving as a carrier. A second planet gear 68 engagesthe agitator sun pinion 56. and is mounted for eccentric rotation withrespect to a support boss I3, while the axis of the gear is constrainedto move along a path concentric with the agitator pinion 56 by a yoke81. The planet gears 68 and 81 are rotatively coupled by a rack andpinion arrangement which enforces equal rotation of the two gears Whileaccommodating relative displacements of their axes. Rotation of thecarrier is then translated into oscillatory displacement of the agitatorshaft 42 by reason of the eccentricity of the axis of the. planet gear68 with respect to its center of rotational support, 1. e. the boss 13.

The planet gear 68 (Figs. 3, 5, and 6) which meshes with the pinion 56on the agitator shaft, is supported by a hub 69 which is slidableradially of the gear, the hub being rotatably supported on an arm 'IIpivoted in the housing. The arm II is formed with a boss I2 at one endthereof which is bored for pivotal movement around one ofthe sleeves 22in the housing. The opposite end of the arm is formed with a cylindricalboss I3 which provides a radial support for the hub 69 within which itis mounted. The hub has a lower flange I4 thereon which is borne by thesurface of the arm circumjacent the boss I3, and has an upper flange I6thereon which supports the gear 68.

The central portion 68a (Figs. 3 and 5) of the web of gear 68 iselevated, and is formed with a slot 1'! therein directed radially of thegear. The upper portion of the hub 69 is formed with a diametral wall I8having a rack I9 machined in the upper surface thereof, the rack beingdisposed in a plane slightly above the flange I6, and being slidablyreceived in the slot 11. Engagement of the rack I9 within the slotconstrains the hub 69 from rotation relative to the gear 68. The rackteeth form a part of the mechanism for shifting the hub 69 radially ofthe gear 68 to vary the eccentricity of the hub with respect to the axisof the gear and the consequent amplitude of the oscillatory motion. Theflange I6 is cut away at one end of the rack bar I8 to permit maximummovement of the hub 69 to the right as will be seen in Fig. 6.

The gear 68 is maintained in mesh with the pinion 56 by a yoke 8I havinga collar 82 at its inner end pivoted on a sleeve 83 on the agitatorshaft 42, and formed with a bore 84 in its outer end which provides abearing for the machined concentric surface 86 at the periphery of theelevated central portion 68a of the planet gear 68.

Under the combined action of the arms 'II and 8|, the planet gear 68 isconstrained with respect to the housing I5 and the agitator shaft 42since its center moves in an are about the shaft, whereas its eccentrichub swings in an are about a sleeve 22 of the housing, that is,substantially radiall of the housing.

The planet gear 81 (Figs. 4, 5, and 6) embodies a bored and faced hub 88journalled on a flanged bearing sleeve 89 fixed in the housing. Thesleeve 89 is formed with a conical bore 99 constituting the seat for aconical fiange 9I struck from the marginal edge of an opening in theupper face I6 of the housing. The parts are retained in assembledrelation by a plug 92 engaged with the flange 9I and threaded into thesleeve. The planet gear 81 meshes with the fixed pinion 93 (Figs. 1 and6) which is retained in the portion 32 of the spider 33, preferably bybeing bonded therein during the die-casting of the member 33.

A stroke-adjusting pinion 94, mounted on the shaft 42, and rotatableindependently of the shaft, is formed integral with the sleeve 83 andwith a sleeve 96 which extends upwardly into the spider 33 through thefixed pinion 93.

The adjusting pinion 94 remains stationary except when the amplitude ofthe oscillation is adjusted. The pinion 94 has the same number of teethas the pinion 93.,

A ring gear 9'1, having the same diameter and number of teeth as theplanet gear 81, is mounted on the lower face of the gear 87 in mesh withthe adjusting pinion 94.

The bore of the ring gear is rotatably received on a turned outer face98 of the web of the planet gear, and is retained thereon by buttons 99threaded into the planet gear, the heads of which overlie the inner edgeof the ring gear.

The means for coupling the two planet gears for concurrent rotation mustaccommodate lateral displacement of the two gears resulting from theeccentricity of the axes of the planet gears. The coupling comprises twoparallel racks IIlI and I02 formed on the upper face of the gear 68, andtwo parallel racks I93 and I94 on the lower face of the gear 81 withinthe ring gear 97. The racks NH and I62 are parallel to, and equallyspaced from, the sliding rack I9 on the hub 69. When the gearing isassembled the racks [Ill and I93 and the racks I92 and I04 are paralleland disposed in face-to-face relation. The intermediate coupling membercomprises a floating shaft I96 having wide-faced pinions I07 and I08splined on each end of the shaft. The pinion I9! meshes with the racksIIlI and I93, and the pinion I98 meshes with the racks I02 and I04.

'I66 and engaged with the faces of the planet gears are provided tomaintain the pinions in ass-asse proper'ilneai relation and preventthe-teeth from bottoming in the racks;

Relative motion between the two planet gears may be considered withrespect to a component parallel to the racks and a component inquadrature to the racks. The parallel component is accommodated byrotation of the pinions: and shaft, the quadrature component by slidingmove ment of the pinions and shaft along; the shaft axis. In thisconnection, the rollers I'99, by engagement with the sides of the racks,prevent the intermediate member from sliding out of engage ment'- withthe racks. pl-anet-ge'ars is possible, since the pinions I9 'I'and1IIlIi are mounted for simultaneous rotation: with the shaft I96.

The-means for varying the eccentricity of the: hub 69 with respect tothe axes of the gear 68- includes, as has been stated, therach 19 on thehub I6. The rack is shifted by a pinion II-I- rotatably mounted on theshaft I66 between the rollers I99. This pinion also meshes with a rackH2 cut in a bar H3 slidably mounted in a diainet'ral path in the lowerface of the gear 81..

The'ends' of the bar I I3 are formed for abutment against the spiral camsurfaces H4 and H5 formed inthe inner edge of the ring gear 81. Thus, byrotating the ring gear with respect to the planet gear, the rack H2 isshifted radially oft he g'ear, rotating thepinion III and shifting therack I9 and hub 69* radially of the lower planet gear.

Normally, the gears 81 and 91 do not rotate relative-to each othenandthe amplitude of cscil.- lation of the shaft 42 remains constant. To ad-'just the amplitudethe pinion 94 isturned, which incidentally may beaccomplished duringthe operation of the machine. The'pinion 94 isintegral with the sleeve 96, the upper end thereof being machined toform a worm wheel II 6 thereon (Figs. 1 and 2) disposed withinthe spider33. A worm I I1, cut into a shaft H8, meshes with and rotates the wormwheel H6. The shaft H8 is enclosed in a cylindrical housingv H9 formed.integral with the spider 33. A pin I2 I: in the hous ing, engaged in agroove [22in the-shaft, retains the shaft against axial displacement.

The outer end of the shaft H8 is coupled, by a shaft'I23 (Fig. 1) anduniversal. joints I24 and I25, to the spindle I26 of an adjusting knob.I21. The spindle I26 is journalled in aboss I28 formed in the flange ofthe frame member I2, and is retained by a star washer I29 secured by anut I3'I. A detent I32 having the inner end thereof seatedupon the bossI28, and its intermediate portion bent to project through an opening I33 in the frame is engaged with the star washer I29. The detent is heldwithin the opening I33 by a compression spring I34 engaged between thehubof the detent and the knob I21. of the knob is machined with a groovetherein which is disposed in telescopic engagement withv acylindricalportion I36 of the frame. By pressing the knob inward, the star washerI29=may be released from the detent, and the shaft.;l23 rotated. Thejoints I24 and I are designedifor suflicient telescopic movement tofacilitate such action.

Alternately, by exerting an outward force against the protruding end I31 of the detent, the: Such operation.

star washer may be released. may be effected by any well known'form'oflinkage which if desired may be associated with a. In this,-

Norelative rotation of-fhe The periphery.

tater shaft will cause the hub 69 to return to the center of the gear68-, terminating the oscillating For this action to take place, the'gears H6 and H1 must be so designed as toibemovement.

reversible.

If desired, the gears I I6 and H1 may be made. irreversible and thedetent mechanism be omitted.v

Preferably, the ratio of gear 8'! to pinion 93 is slightly differentfrom the ratio of gear 68 to pinion 56, with the result that theagitator shaft The amount of creeping. movement may be determined bywell-known will creep slightly.

formulas for the action of compound planetary gears, as set out intheabovementioned copending application.

One or more of sleeves 22- (Fig. 1) opposite the planet gears may beenlarged to balance theweightof the planet gears, or two sets of planetgears in opposite sides of the housing may be provided to secure abalancedmechanism.

' Operation While it is believed the operation of the mechanismdisclosed herein. will be clear to those skilled in the art from theforegoing. des cription, a concise consecutive description of the operation follows.

Assuming that the knob I21 is set for no oscilv lation of the agitatorshaft 42, the hub 69 will .be concentric with the gear 68. If now themotor is energized to rotate the housing I5, the planet gears 81 and 68are revolved around the sunv gears 93 and 56 respectively by the housingI5. The two planet gears are constrained to rotate equal- 1y about theiraxes (that is, with respect to the- By constructing the gearing so thatthese two. pairs of gears are of slightly different ratio, as

stated above, the sun gear 56 and the agitator shaft 42 on which it ismounted will be caused to rotate slowly at a constant rate or creep.

The ring gear 91 is in mesh with the pinion 94.

which remains fixed. Since the pinions 93 and 94 areof the same numberof teeth and the planet gear 81 and ring gear 9'5 are of the same numberof teeth, the gears 81 and 97 rotate together and remain in the samerelative position.

In order to cause oscillation of the agitator shaft 42, the hand wheelI2! is rotated, rotating the pinion 94 through the following chain ofmechanism: shafts I26, I23, and H6, gears H7 and H6, and sleeve 96, withwhich the pinion 94' is integral. This rotation of the pinion 94relative to the fixed pinion 93 causes rotation of the ring gear 91 withrespect to the planet gear 81; and, by this rotation, the bar H3 onwhich the rack I I2 is formed is reciprocated across the face of thegear 81 by the internal cam surfaces H4 and H5 of the ring gear. We mayassume that the movement is sufiicient to shift the rack H2 to'theposition illustrated in Fig. 6. As the rack is moving inwardly, it is inmesh with the pinion II I which thus rotates about the shaft I06. Thepinion I I I meshes with the rack I9 on the hub- 69, shifting the hubaway from the center of the planet gear 68 to an eccentric position suchasillustratedin Fig. 6. This motion of the hub- 69" with respect to thegear 68 is accommodated byrotation of the arm 'H on which the hub 69 isrotatably mounted about its pivot 22 (Fig. 3),;

and by circumferential movement of the gear 68 with respect to thehousing I5. The link I! maintains the hub at a fixed distance from itspivot 22 and the yoke 8i maintains the planet gear 68 at its setdistance from the central axis of the shaft 42. Depending upon theactual angular relation of the planet gears with respect to the housingI5, this shifting movement of the hub will cause more or less rotationof the planet gear 68 with respect to the housing and thus of the sungear 56. This temporary rotation of the sun gear 56 is, of course,communicated to the agitator shaft 42 on which it is mounted. Thisdisplacement just mentioned ceases upon the termination of change in theposition of the hub 69 with respect to the gear 68; but when the hub hasbeen displaced to an off-set position, a continuous oscillating movementof the agitator shaft 42 is produced.

The underlying reason or principle of this action may be more easilyunderstood by reference to the relatively simple mechanism of myabovementioned copending application than by reference to the morecomplex mechanism disclosed here; and it is believed that it will beapparent to anyone who understands the said application.

However, in terms of the structure here presented, the action is asfollows: Rotation of the housing I5 rolls the planet gear 87 and ringgear 9'! as a unit around the fixed pinions 93 and 94, these planetgears rotating on the hub 89 fixed in the housing. The planet gear 68 iscaused to rotate about the eccentric axis defined by the hub 69 atexactly the same rate as the planet gear 81 by the coupling betweenthese two gears comprising the shaft Hi5 and the pinions Ill! and H38fixed thereon. This coupling accommodates relative displacement of theaxes of the gears, however, both by rotation of the pinions I01 and. W8on the racks lfil, I92, I03, and 104, and by sliding movement of thepinions longitudinally of and with the shaft [66, which is permitted bythe fact that the pinions are of greater width than the racks. Theplanet gear 68, therefore, rotates uniformly with the planet gear 8"!whatever the relative positions of the axes of those gears. However,since the axis of rotation of the planet gear 68 defined by the hub 69is eccentric with respect to the axis of the gear 68 and since the axisof the gear 68 is constrained tomove in a circle concentric with theagitator shaft 42, the uniform rotation of the planet gear 68 must causea displacement of the hub 69 about the axis of the gear. By reason ofthe double constraint between the agitator pinion 56 and the planet gear68 imposed by their teeth and the yoke 8|, this displacement of the hub69 is imparted to the agitator pinion as a variable motion, oscillatoryin character. The average rate of rotation of the pinion 56 is eitherzero or a small rate, as previously set out in the description ofoperation of the gearing with the planet gear 68 centered.

The amplitude and frequency of the oscillatory movements and the rate ofthe creeping movement may be determined by the application of knownprinciples of mechanism which have been set out for convenience in myabove-mentioned copending application and need not be repeated here.

It will be apparent to those skilled in the art that for certainapplications where no variation of the amplitude of oscillation isdesired, many of the principles of construction disclosedhereinbeunderstood that the specific terminology is. not intended to berestrictive or confining, and

that various rearrangements of parts and modifications of detail may beresorted to without departing from the scope or spirit of the inventionas herein claimed.

I claim:

1. A variable oscillating gear mechanism comprising two sun gears, aplanet gear meshing with each sun gear, a carrier on which the planetgears are mounted for revolution about the sun gears, means defining anaxis of rotation for one planet gear adjustable radially of the said onegear, and

means coupling the planet gears for concurrent rotation.

2. A variable oscillating gear mechanism comprising two sun gears, oneof the sun gears being fixed, a planet gear meshing with each sun gear,a carrier on which the planet gears are mounted for revolution about thesun gears, means defining an axis of rotation for one planet gearadjustable radially of the said one gear, and

means coupling the planet gears for concurrent rotation.

3. A variable oscillating gear mechanism comprising two coaxial shafts,a sun gear fixed on each shaft, a carrier rotatable about the axis ofthe shafts, a planetgear meshing with each sungear, means constrained torotation about the shaft axis with the carrier defining an axis ofrotation for each planet gear, means coupling the planet gears for equalrotation about their respective axes, and means for adjusting the axisof rotation of one planet gear radially of the said one gear, wherebythe said one gear may be given varying amounts of eccentricity withrespect to that axis.

4. A variable oscillating gear mechanism comprising two coaxial shafts,one of the shafts being fixed, a sun gear fixed on each shaft, acarrierrotatable about the axis of the shafts, a planet gear meshingwith each sun gear, means con-' strained to rotation about the shaftaxis with the carrier defining an axis of rotation for each planet gear,means coupling the planet gears for equal rotation about theirrespective axes, and means for adjusting the axis of rotation of oneplanet gear radially of the said one gear, whereby the said one gear maybe given varying amounts of eccentricity with respect to that axis.

5. A variable oscillating gear mechanism comprising two sun gears, afirst planet gear meshing with one of said sun gears, a second planetgear meshing with the remaining sun gear, said second planet gear havingan eccentric axis of rotation, a carrier in which the said planet gearsare mounted for revolution about the sun gears, means coupling theplanet gears for concurrent rotation about their axes, and means forvarying the axis of eccentricity of the said second planet gearcomprising a member movable radially of the gear,-

a member movable radially of the said first "planet gear, and-meanscoupling the .twomemwith one of said sun gears, a second planet gear ,1

meshing with the remainingsun gear, said second planet gear havinganeccentric axis of rotation, a carrier in which the said planet gears aremounted for revolution .about the :sun gears,

means coupling the planet gears for concurrent rotation about theiraxes, and means for varying the axis of eccentricity of the vsaid secondplanet gear comprising a first member movable radially of the gear, asecond member movable radially of the said first planet gear, meanscoupling the two members, and a part rotatable about the axis of thesaid first planet gear for moving the second member.

7. A variable oscillating gear mechanism comprising two sun gears,afirst planet gear meshing with one of said sun gears, a second planetgear meshing with the remaining sun gear, said :second planet gearhaving an eccentric axis of rotation, a carrier in which the said planetgears are mounted for revolution about the sun gears,

means coupling the planet gears for concurrent rotation about theiraxes, and means for varying the axis of eccentricity of the said-secondplanet gear comprising a first member movable radially of the gear, asecond member movable radially of the said first planet gear, meanscoupling the two members, a gear rotatable about the axis of the saidfirst planet gear for moving the second member, and a pinion rotatableabout the axis of the sun gears for rotating the r last named gear withrespect to the planet gear.

l8. An oscillating gear I mechanism comprising a fixed shaft, arotatable shaft coaxial with the fixed shaft, a housing rotatable on theshafts, a sun gear fixed on each shaft within the housing, a firstplanet gear meshing with one sun gear and rotatable about a shaft fixedin the housing,

a second planet gear meshing with the other sun the shafts, a sun gearfixed on each shaft, a first planet gear meshing with one sun gear androtatable about a shaft fixed in the carrier, a second planet gearmeshing with the other sun gear, a hub for the said second planet gearmounted in the gear for radial movement thereof, said hub beingconstrained with respect to said carrier, a yoke for the second planetgear rotatable about the axis of said coaxial shafts and defining anaxis of rotation for said second planet gear through the axis of thatgear, means coupling the planet gears for concurrent rotation comprisinga rack on each planet gear, each rack being parallel to and opposing therack on the other gear, and a pinion meshing with the racks of bothplanet gears, the pinion being of greater width than the racks; andmeans for varying the eccentricity of the hub of the second planet gearwith respect to the axis of that gear.

10. A variable oscillating gear mechanism comprising two coaxial shafts,a carrier rotatable on 1110 the shafts, a. sun gear fixed on-each shaft,a first planet gear meshing with the fixed sun gear and rotatable abouta 'shaft fixed in the carrier, .a second planet gear meshing with theother sun gear, a hub for the said second planet gear mounted in thegear for radial movement thereof, said hub being constrained withrespect to said carrier, a yoke for the second planet gear rotatableabout the axis of said coaxial shafts and defining an axis of rotationfor said second planet gear through the axis of that gear, meanscoupling the planet gears for concurrent rotation comprising a rack oneach planet gear, each rack being parallel to and opposing the rack :onthe other gear, and a pinion meshing with-the racks of both planetgears, the pinion being of greater width than the racks; and means forvarying the eccentricity of the hub of the second planet gear withrespect .to the axis-of that gear comprising a member slidable radiallyof the first planet gear, a member slidable radially of the secondplanet gear and means coupling the two members. a I

11. An oscillating gear mechanism comprising two coaxial shafts, ahousing rotatable on the shafts, a sun gear fixed on each shaft withinthe housing, a first planet gear meshing with one sun gear and rotatableabout a shaft fixed in the housing, a second planet gear meshing withthe other sun gear, a shaft for the said second planet gear mounted formovement radially of the housing and constrained to rotate therewith;

and means coupling the planet gears for concurrent rotation comprising apair of parallel racks on each planet gear, each rack'being parallel toand in opposition to a rack on the other gear, a floating shaftperpendicular to the racks, and a pinion fixed on each-end of the shaftmeshing with a rack of each planet gear, the'p'inion's being of greaterwidth than the racks.

12. An oscillating gear mechanism comprising a fixed shaft, arotatableshaft coaxial with the fixed shaft, a housing rotatable on the shafts, asun gear fixed oneach shaft within the housing, a first planet gearmeshing with the fixed sun gear and rotatable about a shaft fixed in thehousing, a second planet gear meshing with the rotatable sun gear, ashaft for the said second planet gear mounted for movement radially ofthe housing and constrained to rotate therewith; and means coupling theplanet gears for concurrent rotation comprising a pair of parallel racksa floating shaft perpendicular to the racks, and

a pinion fixed on each end of the shaft meshing with a rack of eachplanet gear, the pinions being of greater width than the racks.

13. A variable oscillating gear mechanism comprising two coaxial shafts,a housing rotatable on the shafts, a sun gear fixed on each shaft, afirst planet gear meshing with one sun gear and rotatable about a shaftfixed in the housing, a second planet gear meshing with the other sungear, a hub for the said second planet gear mounted for movementradially of the housing and constrained to rotate therewith, a yoke forthe said second planet gear for the rotational constraint thereof withrespect to said coaxial shafts, means coupling the planet gears forconcurrent rotation, and means for varying the cocentricity of the hubof the second planet gear with respect to the axis of that gear.

14. A variable oscillating gear mechanism comprising a fixed shaft, arotatable shaft coaxial with the fixed shaft, a housing rotatable on theshafts, a sun gear fixed on each shaft within the housing, a firstplanet gear meshing with the fixed sun gear and rotatable about a shaftfixed in the housing, a second planet gear meshing with the rotatablesun gear, a yoke rotatably mounted about the said coaxial shafts androtatably supporting said second planet gear, a hub for the secondplanet gear mounted in the gear for movement radially thereof andmounted for movement radially of the housing and constrained to rotatetherewith, means coupling the planet gears for concurrent rotation, andmeans for varying the eccentricity of the hub of the second planet gearwith respect to the axis of that gear.

15. A variable oscillating gear mechanism comprising a fixed shaft, arotatable shaft coaxial with the fixed shaft, a housing rotatable on theshafts, a sun gear fixed on each shaft within the housing, a firstplanet gear meshing with the fixed sun gear and rotatable about a shaftfixed in the housing, a second planet gear meshing with the rotatablesun gear, a yoke rotatably mounted about the said coaxial shafts androtatably supporting said second planet gear, a hub for the secondplanet gear mounted in the gear for movement radially thereof andmounted for movement radially of the housing and constrained to rotatetherewith; means coupling the planet gears for concurrent rotationcomprising a pair of parallel racks on each planet gear, each rack beingparallel to and opposing a rack on the other gear, a floating shaftperpendicular to the racks, a pinion fixed on each end of the shaftmeshing with a rack of each planet gear, the pinions being of greaterwidth than the racks; means for varying the eccentricity of the hub ofthe second planet gear comprising a rack slidable radially of the firstplanet gear intermediate the aforementioned racks, a cam and camfollower for shifting the rack, a gear for operating the cam journalledin the housing, a pinion coaxial with the sun gears meshed with the camoperating gear, an actuator for the pinion, a rack on the hub parallelto and opposing the rack slidable on the first planet gear, and a pinionfree on the floating shaft intermediate the pinions fixed thereon andmeshing with the slidable rack and hub rack.

16. A variable oscillating gear mechanism comprising a fixed shaft, arotatable shaft coaxial with the fixed shaft, a housing rotatable on theshafts, the housing being conformed as a pulley, a sun gear fixed oneach shaft Within the housing, a planet gear meshing with each sun gearmounted within the housing and revolvable about the sun gears therewith,means providing one of the planet gears with an axis adjustable radiallyof the gear, and means coupling the planet gears for concurrentrotation.

17. A variable oscillating gear mechanism comprising a fixed shaft, arotatable shaft coaxial with the fixed shaft, a housing rotatable on theshafts, the housing being conformed as a pulley, a sun gear fixed oneach shaft within the housing, a planet gear meshing with each sun gearmounted within the housing and revolvable about the sun gears therewith,means providing one of the planet gear with an axis adjustable radiallyof the gear, and means coupling the planet gears for concurrentrotation, the housing being adapted to retain an oil bath.

JOSEPH D. KREIS.

REFERENCES CITED The following references are of record in the file ofthis patent:

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